Communications networks, such as the Internet, carry a wide variety of traffic. For example, network applications such as email, world wide web, Voice over Internet Protocol (VoIP), multimedia traffic, and many others require access to the network. Different network applications place different demands on the network, as well as presenting different security challenges. For example, VoIP and other real-time data streams require packets to be consistently delivered with relatively short delays, whereas email can tolerate longer delays with much more variability between packets. Efficient use of the network for all network applications requires recognizing the needs of each traffic flow as it traverses the network and maintaining the required performance for each of the various network applications.
The use of the same reference symbols in different drawings indicates similar or identical items.